Electric switch



(No Model.)

Fig.1.

' \NVENT' R MY TGM Mvxesszs 7 d#.Md/wl4 many 9.. Puma-mum, wgemna'ron o c UNITED, STATES PATENT FFICE.

HORACE T. CLARK, OF BRIDGEPORT, CONNECTICUT.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters'Patent No. 449,282, dated March 31, 1891.

Application filed February 25,1891. Serial No. 382,815. [No model.)

To aZZ whom, it may concern:

Be it known that I, HORACE T. CLARK, a citizen of the United States, residing at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Electric Switches; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. This invention relates to certain new and useful improvements in electric switches; but more particularly does it appertain to that portion of the switch whereby the circuit-connections are established.

It is the object of my invent-ion to provide a novel construction of terminal adapted to operate in conjunction with a movable circuit-closing elem ent, which shall be simple in construction and adapted to give a close connection of high conductivity between the parts, and with these ends in view my invention consists in the construction and combination of elements hereinafter fully explained and then recited in theclairns.

In the drawings which are hereunto annexed, and which form a part of this specification, Figurel is a side elevation of a switch provided with my invention. Fig. 2 represents in perspective the terminals and the end of the circuit-closer, the parts being out of contact. Fig. 3 shows the circuit as completed, the parts being in end elevation.

1 represents the base upon which several parts of the switch are supported. The terminals consist of the blocks 2, preferably of cast metal, each of which has an upward projection 3, rounded as to its upper end. The opposed faces of the two terminals are nearly vertical. Upon each of these terminal-blocks ,are secured spring-contact brushes 4, preferably consisting of two or more thin sheets of conductive metal, such as copper, and these may be split lengthwise into fingers. At their outer ends said brushes are riveted or otherwise firmly secured, as at 5, to the out side surfaces of the projections 3, and from their point of attachment they follow the contour of said projections, lying smoothly. against them until, after passing over their rounded upper ends, they extend downward and outward in aline tangent to the curve of the top of the terminal.

6 is the circuit-closer, whose end is formed in section in the shape of a truncated wedge, of such size that when driven downward between the spring-bearing terminals, its thickest portion will fit snugly between the upper ends of said terminals where the springs are supported in contact with the blocks. When the parts are so engaged, the free ends of the contact-brushes lie closely against the tapered faces of the circuit-closer, pressing against them from opposite sides with a force dependent upon the spring quality of the metal used. It will be observed, also, that the rounded upper surface over which the spring passes forms a fulcrum for it and thus somewhat enhances its resilience.

The switch (shown at Fig. 1) is shown as double pole; but my present invention has nothing to do with the cons'tructiouof switch, but merely relates to the terminals. Said switch may therefore be sufficiently described as consisting of the movable circuit-closer heretofore referred to, a housing 7, in which it is guided, and a handle 8, by which it may be manipulated for making and breaking contact.

In the double-pole switch it is essential that the two ends of the circuit-closer be insulated one from the other, and this I do by interposing a non-conducting sleeve or block between the bar and the wedge-shaped extremity, or in other desired or usual manner. In the single-pole switch it is of course not essential that the circuit-making end of the bar should be insulated, but it is preferable. This question of insulation, however, is immaterial so far as the essentials of my invention are concerned.

I am aware that terminals having springcontacts thereon are not new, and I do not therefore wish to be understood as laying claim, broadly, to the use of resilient ter= minals or of terminals other than those having characteristics now to be pointed out in the claims.

I claim 1. The combination, with the base, of the terminal-blocks having opposed faces, the contact-brushes having their ends secured to the rear side of the blocks and extending over the ends of said blocks and then obliquely downward and outward therefrom, and a circuit-closer in the form of a truncated wedge, and means for driving it downward between the terminals.

2. The terminal-blocks 2, having projections 3, in combination with the springs 4, secured to the rear sides of said blocks, as at 5, and extending downward over the faces of said blocks, as shown, and the circuit-closer having oblique convergent faces, and means for forcing it into engagement, substantially as and for the purpose specified.

3. The combination, with the base, of the terminal-blocks 2, having upward projections rounded upon their top ends, contact-springs secured at the rear side of the projections and following the contour thereof over their ends and then extending downward and outward in a line tangent to their curves, and a circuit-closerin the form of a truncated Wedge, and means for driving it down between the terminals, substantially as and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

HORACE T. CLARK.

Witnesses:

SHERMAN HARTWELL HUBBARD, M. O. I-IINoHoLIFFE. 

